引用: 脑洞大赛9 发表于 2018-11-13 20:52
> {quote:title = drkirkby写道:} {quote}>端口扩展避免你购买另一个VNA或一些10,000美元的软件,但我怀疑它是否像自动夹具一样准确,虽然我不知道多么聪明
那是。
>> Dave AFR代码支持两种模式:仅2端口或1端口AFR,仅打开或仅打开。
> {quote:title = Dr_joel写道:} {quote} >> {quote:title = drkirkby写道:} {quote} >>>端口扩展可以避免你购买另一个VNA或一些10,000美元的软件,但我对此表示怀疑
和自动夹具拆卸一样准确,虽然我不知道它有多聪明。
>>>> Dave >> AFR代码支持两种模式:仅2端口或1端口AFR,仅打开或短路。
两个版本通过计算适配器的完整s2p文件完全纠正所有适配器的错误,包括输入匹配,输出匹配和S21 mag和相位(我们假设S21 = S12)。
显然比我使用的端口扩展要好很多!
>它依赖于我认为会有时域变换的组合 - 你的书中有一些关于这类事情的信息。
>和“其他数据处理”以获得这些值。
魔术!
>它还要求灯具在DUT接口附近具有恒定阻抗(不一定是50欧姆但是恒定)。
这里“附近”表示没有表示分析仪最高频率的4个上升时间的距离。
对于26.5 GHz分析仪,如果我正确计算,这相当于大约2.25厘米(小于1英寸)。
也就是说,固定装置应该在靠近dut的恒定阻抗线上长约1英寸。
如果使用50 GHz分析仪,则可将其推至约1 cm。
您可以在夹具上使用更高的频率测量一次来计算AFR结果,然后获取S2P文件并在较低频率的分析仪上使用它进行持续测试。
如果我错了,请纠正我,但是导出的S参数AFR不一定是参考平面,这可能导致重大错误。
我在这个例子中使用了一个“N”连接器,原因我猜对你很明显,但原理是一样的。
假设有一个26.5 GHz 3.5 mm校准套件而不是N cal套件,但是想要测试一个N型设备。
可以用3.5 mm进行校准,然后使用一端为3.5 mm的适配器,另一端使用N型。
如果对适配器进行单端口测量,则使用自动夹具移除,我认为会出现严重错误,因为阴N的引脚末端距参考平面约5 mm - 外导体配合平面。
我对么?
(同样令人怀疑的是,适配器能够满足高达18 GHz的恒定阻抗条件,但这是另一个问题,但对于UFL适配器也是如此。这些都是几个$ s,所以不完全是精密设备。
)我不认为这对于U.FL的SMA是一个问题,因为连接器的参考平面几乎与母针的末端处于相同的位置。
我有兴趣知道是否可以使用AFR来测量BNC DUT,使用1)20 GHz VNA 2)85054B 18 GHz N cal套件3)N到BNC适配器作为夹具的组合。
4)N1930B物理层测试系统(PLTS)在单端口模式下,BNC连接器刚刚打开。
我拥有1-3,并且知道有PLTS的人。
如果没有BNC连接器在我面前,我不确定引脚相对于参考平面的位置,但我知道N,母中心导体的末端远离参考平面。
戴夫
以上来自于谷歌翻译
以下为原文
> {quote:title=Dr_joel wrote:}{quote}
> > {quote:title=drkirkby wrote:}{quote}
>
> > The port extension avoids you buying another VNA or a bit of $10,000 software, but I doubt it it as accurate as the automatic fixture removal, although I don't know how clever that is.
> >
> > Dave
>
> The AFR code supports two modes: 2-port thru only, or 1 port AFR with either open only or short only. Both versions fully correct for all the adapter's errors by computing the full s2p file for the adapter including input match, output match and S21 mag and phase (we presume S21=S12).
Obviously a lot better than the port extension I have used!
> It relies on a combination of time-domain transforms
I thought it would - there is some info in your book about this sort of thing.
> and "other data processing" to obtain these values.
The magic!
> It also requires that the fixture be of constant impedance (not necessarily 50 ohms but constant) in the vicinity of the DUT interface. Here "vicinity" means without about a distance that represents 4 risetimes of the highest frequency of the analyzer. For a 26.5 GHz analyzer, this amounts to about 2.25 cm (less than 1 inch) if I figure it correctly. That is, the fixture should have a constant impedance line near the dut that is about 1 inch long. If you use a 50 GHz analyzer, you can push that down to about 1 cm. You can use a higher freq measurement on a fixture one time to compute the AFR result, then take the S2P file and use it on a lower frequency analyzer for ongoing test.
Correct me if I am wrong, but the S-parameters AFR derives are not necessarily to the reference plane, which could lead to significant errors. I use an "N" connector in this example for reasons I guess are obvious to you, but the principle is the same.
Lets assume one had a 26.5 GHz 3.5 mm cal kit and not an N cal kit, but wanted to test a male N device. One could calibrate with 3.5 mm, then use an adapter with 3.5 mm one end, and female N on the other. If one does a one port measurement of the adapter, then used the automatic fixture removal, I think there would be serious errors as the end of the pin of the female N is about 5 mm away from the reference plane - outer conductor mating plane.
Am I correct? (It's also doubtful the adapter would meet the condition of constant impedance up to 18 GHz, but that is another issue, but the same could be said for the UFL adapter. These are a few $s each, so not exactly a precision device. )
I don't see this being an issue with an SMA to U.FL, as the reference plane of the connector is pretty much in the same position as the end of the female pin.
I'd be interested to know if one could use the AFR to measure a BNC DUT using a combination of
1) 20 GHz VNA
2) 85054B 18 GHz N cal kit
3) N to BNC adapter as a fixture.
4) N1930B Physical Layer Test System (PLTS) in one-port mode with the BNC connector just open.
I own 1-3, and know someone with PLTS.
Without a BNC connector in front of me, I'm not exactly sure where the pins are relative to the reference plane, but I know for an N, the end of the female centre conductor is nowhere near the reference plane.
Dave
引用: 脑洞大赛9 发表于 2018-11-13 20:52
> {quote:title = drkirkby写道:} {quote}>端口扩展避免你购买另一个VNA或一些10,000美元的软件,但我怀疑它是否像自动夹具一样准确,虽然我不知道多么聪明
那是。
>> Dave AFR代码支持两种模式:仅2端口或1端口AFR,仅打开或仅打开。
> {quote:title = Dr_joel写道:} {quote} >> {quote:title = drkirkby写道:} {quote} >>>端口扩展可以避免你购买另一个VNA或一些10,000美元的软件,但我对此表示怀疑
和自动夹具拆卸一样准确,虽然我不知道它有多聪明。
>>>> Dave >> AFR代码支持两种模式:仅2端口或1端口AFR,仅打开或短路。
两个版本通过计算适配器的完整s2p文件完全纠正所有适配器的错误,包括输入匹配,输出匹配和S21 mag和相位(我们假设S21 = S12)。
显然比我使用的端口扩展要好很多!
>它依赖于我认为会有时域变换的组合 - 你的书中有一些关于这类事情的信息。
>和“其他数据处理”以获得这些值。
魔术!
>它还要求灯具在DUT接口附近具有恒定阻抗(不一定是50欧姆但是恒定)。
这里“附近”表示没有表示分析仪最高频率的4个上升时间的距离。
对于26.5 GHz分析仪,如果我正确计算,这相当于大约2.25厘米(小于1英寸)。
也就是说,固定装置应该在靠近dut的恒定阻抗线上长约1英寸。
如果使用50 GHz分析仪,则可将其推至约1 cm。
您可以在夹具上使用更高的频率测量一次来计算AFR结果,然后获取S2P文件并在较低频率的分析仪上使用它进行持续测试。
如果我错了,请纠正我,但是导出的S参数AFR不一定是参考平面,这可能导致重大错误。
我在这个例子中使用了一个“N”连接器,原因我猜对你很明显,但原理是一样的。
假设有一个26.5 GHz 3.5 mm校准套件而不是N cal套件,但是想要测试一个N型设备。
可以用3.5 mm进行校准,然后使用一端为3.5 mm的适配器,另一端使用N型。
如果对适配器进行单端口测量,则使用自动夹具移除,我认为会出现严重错误,因为阴N的引脚末端距参考平面约5 mm - 外导体配合平面。
我对么?
(同样令人怀疑的是,适配器能够满足高达18 GHz的恒定阻抗条件,但这是另一个问题,但对于UFL适配器也是如此。这些都是几个$ s,所以不完全是精密设备。
)我不认为这对于U.FL的SMA是一个问题,因为连接器的参考平面几乎与母针的末端处于相同的位置。
我有兴趣知道是否可以使用AFR来测量BNC DUT,使用1)20 GHz VNA 2)85054B 18 GHz N cal套件3)N到BNC适配器作为夹具的组合。
4)N1930B物理层测试系统(PLTS)在单端口模式下,BNC连接器刚刚打开。
我拥有1-3,并且知道有PLTS的人。
如果没有BNC连接器在我面前,我不确定引脚相对于参考平面的位置,但我知道N,母中心导体的末端远离参考平面。
戴夫
以上来自于谷歌翻译
以下为原文
> {quote:title=Dr_joel wrote:}{quote}
> > {quote:title=drkirkby wrote:}{quote}
>
> > The port extension avoids you buying another VNA or a bit of $10,000 software, but I doubt it it as accurate as the automatic fixture removal, although I don't know how clever that is.
> >
> > Dave
>
> The AFR code supports two modes: 2-port thru only, or 1 port AFR with either open only or short only. Both versions fully correct for all the adapter's errors by computing the full s2p file for the adapter including input match, output match and S21 mag and phase (we presume S21=S12).
Obviously a lot better than the port extension I have used!
> It relies on a combination of time-domain transforms
I thought it would - there is some info in your book about this sort of thing.
> and "other data processing" to obtain these values.
The magic!
> It also requires that the fixture be of constant impedance (not necessarily 50 ohms but constant) in the vicinity of the DUT interface. Here "vicinity" means without about a distance that represents 4 risetimes of the highest frequency of the analyzer. For a 26.5 GHz analyzer, this amounts to about 2.25 cm (less than 1 inch) if I figure it correctly. That is, the fixture should have a constant impedance line near the dut that is about 1 inch long. If you use a 50 GHz analyzer, you can push that down to about 1 cm. You can use a higher freq measurement on a fixture one time to compute the AFR result, then take the S2P file and use it on a lower frequency analyzer for ongoing test.
Correct me if I am wrong, but the S-parameters AFR derives are not necessarily to the reference plane, which could lead to significant errors. I use an "N" connector in this example for reasons I guess are obvious to you, but the principle is the same.
Lets assume one had a 26.5 GHz 3.5 mm cal kit and not an N cal kit, but wanted to test a male N device. One could calibrate with 3.5 mm, then use an adapter with 3.5 mm one end, and female N on the other. If one does a one port measurement of the adapter, then used the automatic fixture removal, I think there would be serious errors as the end of the pin of the female N is about 5 mm away from the reference plane - outer conductor mating plane.
Am I correct? (It's also doubtful the adapter would meet the condition of constant impedance up to 18 GHz, but that is another issue, but the same could be said for the UFL adapter. These are a few $s each, so not exactly a precision device. )
I don't see this being an issue with an SMA to U.FL, as the reference plane of the connector is pretty much in the same position as the end of the female pin.
I'd be interested to know if one could use the AFR to measure a BNC DUT using a combination of
1) 20 GHz VNA
2) 85054B 18 GHz N cal kit
3) N to BNC adapter as a fixture.
4) N1930B Physical Layer Test System (PLTS) in one-port mode with the BNC connector just open.
I own 1-3, and know someone with PLTS.
Without a BNC connector in front of me, I'm not exactly sure where the pins are relative to the reference plane, but I know for an N, the end of the female centre conductor is nowhere near the reference plane.
Dave
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